METastasis Reporting and Data System for Prostate Cancer as a Prognostic Imaging Marker in Castration-resistant Prostate Cancer.

METastasis Reporting and Data System for Prostate Cancer (MET-RADS-P) has been proposed as a standard of data acquisition and interpretation for whole-body diffusion-weighted magnetic resonance imaging (WB-DWI) performed in men with advanced prostate cancer. The aim of this study is to demonstrate the clinical significance of the scores in castration-resistant prostate cancer (CRPC).

We retrospectively evaluated WB-DWI obtained from 72 patients with CRPC between 2014 and 2017, when disease progression was suspected at the time of starting a new line of anticancer therapy. Twenty-five (35%) and 30 (42%) patients had a treatment history that included taxane-based chemotherapy and new hormonal drugs, respectively.

Active bone metastases were identified in 60 patients (83%; number of bone metastasis = 0, 1-2, 3-5, 6-10, and > 10: n = 12 [17%], 20 [28%], 11 [15%], 1 [1%], and 28 [39%], respectively). Progressive lymph node and visceral metastases were identified in 10 (14%) and 4 (6%), respectively. During the median follow-up period of 24 months, 36 (50%) died of prostate cancer. Cancer-specific survival (CSS) was significantly stratified according to the MET-RADS-P scores of osseous metastatic burden and the presence of visceral metastasis (P < .0001). Multivariate analysis revealed that high osseous metastatic burden (> 10) and the presence of visceral metastasis were significant indicators of shorter CSS (P = .0036 and P = .0017, respectively).

The extent of bone metastasis and the presence of visceral metastasis on WB-DWI were associated with a shorter CSS in CRPC. MET-RADS-P score can be a prognostic imaging biomarker for CRPC.

Clinical genitourinary cancer. 2019 Dec 14 [Epub ahead of print]

Soichiro Yoshida, Taro Takahara, Chikako Ishii, Yuki Arita, Yuma Waseda, Toshiki Kijima, Minato Yokoyama, Junichiro Ishioka, Yoh Matsuoka, Kazutaka Saito, Yasuhisa Fujii

Department of Urology, Tokyo Medical and Dental University Graduate School, Tokyo, Japan. Electronic address: ., Department of Biomedical Engineering, Tokai University School of Engineering, Tokyo, Japan; AIC Yaesu Clinic, Tokyo, Japan., AIC Yaesu Clinic, Tokyo, Japan., AIC Yaesu Clinic, Tokyo, Japan; Department of Diagnostic Radiology, Keio University School of Medicine, Tokyo, Japan., Department of Urology, Tokyo Medical and Dental University Graduate School, Tokyo, Japan.